This year marks the 40th anniversary of the controversial Rockefeller drug laws. In 1973, New York City was suffering a heroin epidemic. And in response, Gov. Nelson Rockefeller pushed for long prison sentences, even for low-level drug dealers and addicts. The policy changed the way we think about crime and punishment. It influenced tough-on-crime laws across the country, and it contributed to the sharp rise in the number of Americans behind bars. As North Country Public Radio's Brian Mann reports, a fresh debate is now under way over the cost, fairness and effectiveness of Rockefeller-style laws.

BRIAN MANN, BYLINE: There are roughly half a million people behind bars for non-violent drug crimes right now, in America. But the truth is, no one really knows how many people have been sentenced to long prison bids since the Rockefeller laws first passed 40 years ago. What's clear is that tough sentencing laws shaped a generation of young men, especially black and Hispanic men like George Prendes.

GEORGE PRENDES: It's just the drudgery. I mean, at my age, I shouldn't be struggling like this.

MANN: Prendes, who's 59 now, was born in Cuba. He works long hours as a telemarketer, barely making rent on his tiny, cluttered apartment in the Bronx. His wife, Yvonne, says prison carved a hole in the middle of Prendes' life.

YVONNE PRENDES: His experience damaged a part of him, you know, wanting to recuperate the time lost. And you just can't do that. You know, you can't get those 15 years back.

MANN: Prendes was in his early 20s when New York's legislature set strict mandatory minimum prison sentences of 15 years to life for non-violent drug crimes. Prendes says he had no idea the rules were changing.

G. PRENDES: Everybody was doing cocaine. And I met judges, I met lawyers, I met a lot of affluent people, and to me that was a sign of affluence. So I did a little coke here and there.

MANN: Prendes says he was broke, facing eviction from his apartment. So in 1977, he made the big mistake that put him in the cross hairs of the new laws. He agreed to help with a drug deal, selling a pound of cocaine upstate in Rochester, New York. It was a sting.

G. PRENDES: They bust down the door, and there's like, 20 cops in the other room. They came in. I remember, the guy walked right up to me. I was stunned. And the guy punched me right in the face.

MANN: The way Prendes tells it, he had no idea, at first, that the new Rockefeller law was sending thousands more people to prison every year for longer prison sentences. The guy who did understand the consequences was Robert King, the young assistant district attorney assigned to prosecute Prendes.

ROBERT KING: I felt very comfortable with - first with the conviction. I mean, I think the evidence in the case clearly supported his conviction. The sentencing rules were what they were so it was kind of out of my hands, really.

MANN: Advocates of lengthy prison sentences, including many prosecutors, are convinced that they deter crime and slow the spread of illegal drugs. Prendes was a first-time offender, and no one saw him as a kingpin drug dealer. But under the Rockefeller law, he spent the next decade and a half in maximum security prison with no chance for parole.

MERCEDES PRENDES: I don't know if people realize that with a sentence like that, it takes away not only from the person; it takes away from a family.

MANN: Prendes' sister Mercedes is in her 50s now, but was a teenager when he went away to prison. She says their mother spent years, and all the family's money, trying to help her brother.

M. PRENDES: It really dismantled - it was like a bomb. It had profound effects that you don't come back from.

MANN: In a way, the Prendes family's experience is a new part of the American story. Mandatory minimum sentencing rules for drugs and other non-violent crimes are now on the books in almost every state, and nearly half the inmates in federal prison are serving time on drug charges. Studies show the overwhelming majority of people sentenced under Rockefeller-style laws are black and Hispanic men, despite the fact that there's a lot of drug use in white communities.

KING: I think the intentions were good. Whether or not it achieved the results, I'd say that they have not.

MANN: Robert King, who put Prendes behind bars, is part of a growing movement of one-time supporters of mandatory prison sentences who now say they have doubts about their effectiveness and their fairness.

KING: I have a son who's about to turn 30. And so we were talking about this case, and he was enraged by the sentence. He said, that's ridiculous. And I think by today's standards, I think most people would look at this - and I guess I would look at it - and say that sentence was disproportionate.

MANN: Rockefeller-style laws are still the norm in the U.S., with more than 2.3 million Americans behind bars. And incarceration rates are still rising in some states. But the high cost of operating prisons has caused other states to ease sentencing rules, leading to significant declines in inmate populations in California and New York. Under New York's modified sentencing guidelines, passed in 2009, George Prendes might have served as little as a year behind bars before being released for parole or sent for drug counseling.

G. PRENDES: You try not to be bitter. I mean, I was 23 years old when I got arrested. I got out of prison when I was 37. That was a big chunk of my life, and there's a lot of things that I could have done and didn't do.

MANN: So while politicians and prosecutors debate the future of Rockefeller-style laws, millions of former inmates, like George Prendes, are sorting out what they can salvage after decades spent in prison.

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